AllTheRooms.com's Monthly Vacation Rental Index tracks
accommodations volume and price trends in the top 25 US cities.
Each month it publishes a new update that will show "the hottest
vacation markets, along with trends in accommodation count and
type, average rate, and availability".

The company says it can compile the report due to its ability to
search every single available accommodation from sites such as
Airbnb, Priceline, Expedia, Tripadvisor, VRBO, HomeAway, and
hundreds of others to identify total vacation rental availability
worldwide.

In the December report, the top 10 markets by property volume were
New York City, Los Angeles, Austin, San Diego, Washington, Houston,
Philadelphia, Seattle, San Francisco and Chicago. The highest
median rate from the top 25 was recorded by San Francisco ($190),
with the lowest in Dallas ($88.32).

New York also had the highest number of "Instant Book" properties
- those which, like hotel rooms, do not require the renter to wait
for host approval before finalising the booking. It had 12,000
instant book properties, followed by LA with 9,323 and Houston with
4,133.